331
FNCA52 TJSJ 171930
FWFSJU
FIRE WEATHER PLANNING FORECAST FOR PUERTO RICO
NATIONAL WEATHER SERVICE SAN JUAN PR
330 PM AST THU SEP 17 2026
DISCUSSION
NO FIRE DANGER IS EXPECTED TODAY.
PRZ014-180800-
SOUTHEAST COASTAL PLAINS-
330 PM AST THU SEP 17 2026
TONIGHT FRI FRI NIGHT SAT
CLOUD COVER PCLDY PCLDY MCLEAR PCLDY
PRECIP TYPE SHOWERS SHOWERS SHOWERS SHOWERS
CHANCE PRECIP (%) 40 30 20 10
TEMP (24H TREND) 75 (-2) 91 (+2) 75 91
RH % (24H TREND) 94 (+1) 53 (-16) 89 49
WIND 20FT/EARLY(MPH) E 12 E 12 E 11 E 13
WIND 20FT/LATE(MPH) E 11 SE 14 NE 9 SE 14
MIXING HGT(FT-AGL/MSL) 4870 4830
TRANSPORT WND (MPH) E 14 E 13
VENT RATE (KT-FT) 58440 53130
DISPERSION 5 5
DSI 5 6 3 6
RH RECOVERY EXCELLENT EXCELLENT
REMARKS...NONE.
PRZ015-180800-
SOUTHERN HILLS-
330 PM AST THU SEP 17 2026
TONIGHT FRI FRI NIGHT SAT
CLOUD COVER PCLDY PCLDY PCLDY PCLDY
PRECIP TYPE SHOWERS SHOWERS SHOWERS SHOWERS
CHANCE PRECIP (%) 40 40 20 20
TEMP (24H TREND) 72 (-3) 89 (+4) 72 89
RH % (24H TREND) 98 (+2) 60 (-13) 97 61
WIND 20FT/EARLY(MPH) E 10 E 11 E 10 E 10
WIND 20FT/LATE(MPH) E 10 SE 11 E 10 SE 11
MIXING HGT(FT-AGL/MSL) 5530 5530
TRANSPORT WND (MPH) E 13 E 12
VENT RATE (KT-FT) 60830 55300
DISPERSION 5 5
DSI 4 6 2 6
RH RECOVERY EXCELLENT EXCELLENT
REMARKS...NONE.
PRZ016-180800-
NORTH COASTAL PLAINS-
330 PM AST THU SEP 17 2026
TONIGHT FRI FRI NIGHT SAT
CLOUD COVER PCLDY PCLDY PCLDY PCLDY
PRECIP TYPE SHOWERS SHOWERS SHOWERS TSTMS
CHANCE PRECIP (%) 50 40 40 40
TEMP (24H TREND) 75 (-2) 93 (+2) 75 92
RH % (24H TREND) 99 (+2) 59 (-7) 98 61
WIND 20FT/EARLY(MPH) E 13 E 12 E 16 E 11
WIND 20FT/LATE(MPH) E 10 E 18 SE 10 E 17
MIXING HGT(FT-AGL/MSL) 5200 4860
TRANSPORT WND (MPH) E 13 E 12
VENT RATE (KT-FT) 57200 48600
DISPERSION 5 5
DSI 5 6 5 6
RH RECOVERY EXCELLENT EXCELLENT
REMARKS...NONE.
PRZ017-180800-
NORTHERN HILLS-
330 PM AST THU SEP 17 2026
TONIGHT FRI FRI NIGHT SAT
CLOUD COVER PCLDY PCLDY PCLDY PCLDY
PRECIP TYPE SHOWERS SHOWERS SHOWERS TSTMS
CHANCE PRECIP (%) 40 40 30 60
TEMP (24H TREND) 72 (-2) 91 (+2) 72 91
RH % (24H TREND) 99 (0) 59 (-7) 98 62
WIND 20FT/EARLY(MPH) E 12 E 11 E 12 E 10
WIND 20FT/LATE(MPH) E 8 E 14 SE 8 E 13
MIXING HGT(FT-AGL/MSL) 5180 5490
TRANSPORT WND (MPH) E 9 E 9
VENT RATE (KT-FT) 41440 43920
DISPERSION 5 5
DSI 4 6 3 6
RH RECOVERY EXCELLENT EXCELLENT
REMARKS...NONE.
PRZ018-180800-
WEST COAST-
330 PM AST THU SEP 17 2026
TONIGHT FRI FRI NIGHT SAT
CLOUD COVER PCLDY PCLDY PCLDY PCLDY
PRECIP TYPE SHOWERS SHOWERS SHOWERS TSTMS
CHANCE PRECIP (%) 40 50 50 50
TEMP (24H TREND) 75 (-1) 93 (+1) 75 94
RH % (24H TREND) 98 (+2) 59 (-8) 97 59
WIND 20FT/EARLY(MPH) E 13 E 12 E 12 E 10
WIND 20FT/LATE(MPH) E 12 E 13 E 9 E 11
MIXING HGT(FT-AGL/MSL) 4140 4760
TRANSPORT WND (MPH) E 9 E 8
VENT RATE (KT-FT) 33120 33320
DISPERSION 5 5
DSI 5 6 3 6
RH RECOVERY EXCELLENT EXCELLENT
REMARKS...NONE.
PRZ019-180800-
EASTERN INTERIOR-
330 PM AST THU SEP 17 2026
TONIGHT FRI FRI NIGHT SAT
CLOUD COVER PCLDY PCLDY PCLDY PCLDY
PRECIP TYPE SHOWERS SHOWERS SHOWERS TSTMS
CHANCE PRECIP (%) 50 50 50 40
TEMP (24H TREND) 73 (-3) 91 (+4) 73 91
RH % (24H TREND) 99 (+2) 59 (-11) 98 60
WIND 20FT/EARLY(MPH) E 12 E 11 E 10 E 10
WIND 20FT/LATE(MPH) E 12 E 12 E 10 E 12
MIXING HGT(FT-AGL/MSL) 6620 6180
TRANSPORT WND (MPH) E 13 E 10
VENT RATE (KT-FT) 72820 55620
DISPERSION 5 5
DSI 4 6 3 6
RH RECOVERY EXCELLENT EXCELLENT
REMARKS...NONE.
PRZ022-180800-
LUQUILLO MOUNTAIN RANGE-
330 PM AST THU SEP 17 2026
TONIGHT FRI FRI NIGHT SAT
CLOUD COVER PCLDY PCLDY MCLDY PCLDY
PRECIP TYPE SHOWERS SHOWERS SHOWERS SHOWERS
CHANCE PRECIP (%) 50 60 60 40
TEMP (24H TREND) 71 (-3) 86 (+4) 71 86
RH % (24H TREND) 99 (0) 65 (-12) 100 65
WIND 20FT/EARLY(MPH) E 10 E 10 E 8 E 9
WIND 20FT/LATE(MPH) E 9 E 10 E 8 E 10
MIXING HGT(FT-AGL/MSL) 4660 4480
TRANSPORT WND (MPH) E 14 E 10
VENT RATE (KT-FT) 55920 40320
DISPERSION 5 5
DSI 5 6 5 6
RH RECOVERY EXCELLENT EXCELLENT
REMARKS...NONE.
PRZ023-180800-
CENTRAL MOUNTAIN RANGE-
330 PM AST THU SEP 17 2026
TONIGHT FRI FRI NIGHT SAT
CLOUD COVER PCLDY PCLDY MCLEAR PCLDY
PRECIP TYPE SHOWERS SHOWERS SHOWERS TSTMS
CHANCE PRECIP (%) 40 50 40 60
TEMP (24H TREND) 70 (-2) 88 (+5) 69 88
RH % (24H TREND) 99 (+1) 60 (-15) 98 64
WIND 20FT/EARLY(MPH) E 8 E 9 E 9 E 8
WIND 20FT/LATE(MPH) E 6 E 9 E 6 E 8
MIXING HGT(FT-AGL/MSL) 6000 6070
TRANSPORT WND (MPH) E 7 E 8
VENT RATE (KT-FT) 36000 42490
DISPERSION 5 5
DSI 2 6 1 6
RH RECOVERY EXCELLENT EXCELLENT
REMARKS...NONE.
PRZ024-180800-
CAYEY MOUNTAIN RANGE-
330 PM AST THU SEP 17 2026
TONIGHT FRI FRI NIGHT SAT
CLOUD COVER PCLDY PCLDY PCLDY PCLDY
PRECIP TYPE SHOWERS SHOWERS SHOWERS SHOWERS
CHANCE PRECIP (%) 40 50 50 40
TEMP (24H TREND) 72 (-1) 86 (+4) 72 86
RH % (24H TREND) 100 (+1) 66 (-11) 99 66
WIND 20FT/EARLY(MPH) E 9 E 10 E 8 E 9
WIND 20FT/LATE(MPH) E 9 E 10 E 8 E 10
MIXING HGT(FT-AGL/MSL) 5280 5320
TRANSPORT WND (MPH) E 14 E 12
VENT RATE (KT-FT) 63360 53200
DISPERSION 5 5
DSI 5 6 4 6
RH RECOVERY EXCELLENT EXCELLENT
REMARKS...NONE.
PRZ025-180800-
VIEQUES-
330 PM AST THU SEP 17 2026
TONIGHT FRI FRI NIGHT SAT
CLOUD COVER PCLDY PCLDY PCLDY PCLDY
PRECIP TYPE SHOWERS SHOWERS SHOWERS SHOWERS
CHANCE PRECIP (%) 40 40 50 40
TEMP (24H TREND) 79 (-1) 90 (0) 78 90
RH % (24H TREND) 87 (-1) 59 (-4) 86 57
WIND 20FT/EARLY(MPH) E 14 E 13 E 12 E 10
WIND 20FT/LATE(MPH) E 13 E 12 E 12 E 10
MIXING HGT(FT-AGL/MSL) 3320 3160
TRANSPORT WND (MPH) E 16 E 13
VENT RATE (KT-FT) 46480 34760
DISPERSION 5 5
DSI 6 6 6 6
RH RECOVERY EXCELLENT EXCELLENT
REMARKS...NONE.
PRZ026-180800-
CULEBRA-
330 PM AST THU SEP 17 2026
TONIGHT FRI FRI NIGHT SAT
CLOUD COVER PCLDY PCLDY PCLDY PCLDY
PRECIP TYPE SHOWERS SHOWERS SHOWERS SHOWERS
CHANCE PRECIP (%) 40 40 50 40
TEMP (24H TREND) 79 (-2) 91 (+2) 79 91
RH % (24H TREND) 89 (0) 61 (-7) 90 59
WIND 20FT/EARLY(MPH) E 14 E 12 E 12 E 11
WIND 20FT/LATE(MPH) E 13 E 11 E 12 E 11
MIXING HGT(FT-AGL/MSL) 3100 3210
TRANSPORT WND (MPH) E 17 E 14
VENT RATE (KT-FT) 46500 38520
DISPERSION 5 5
DSI 6 6 6 6
RH RECOVERY EXCELLENT EXCELLENT
REMARKS...NONE.
PRZ027-180800-
SOUTHWEST COASTAL PLAINS AND MONA ISLAND-
330 PM AST THU SEP 17 2026
TONIGHT FRI FRI NIGHT SAT
CLOUD COVER PCLDY MCLEAR MCLEAR MCLEAR
PRECIP TYPE SHOWERS SHOWERS SHOWERS SHOWERS
CHANCE PRECIP (%) 40 10 20 10
TEMP (24H TREND) 76 (-2) 93 (+2) 76 93
RH % (24H TREND) 93 (+2) 52 (-12) 89 48
WIND 20FT/EARLY(MPH) E 18 E 18 E 14 E 14
WIND 20FT/LATE(MPH) E 17 SE 19 E 13 SE 16
MIXING HGT(FT-AGL/MSL) 3900 4810
TRANSPORT WND (MPH) E 15 E 14
VENT RATE (KT-FT) 50700 57720
DISPERSION 5 5
DSI 6 6 4 6
RH RECOVERY EXCELLENT EXCELLENT
REMARKS...NONE.
VIZ001-180800-
SAINT THOMAS AND SAINT JOHN-
330 PM AST THU SEP 17 2026
TONIGHT FRI FRI NIGHT SAT
CLOUD COVER PCLDY PCLDY PCLDY PCLDY
PRECIP TYPE SHOWERS SHOWERS SHOWERS SHOWERS
CHANCE PRECIP (%) 30 40 40 40
TEMP (24H TREND) 79 (-1) 89 (+2) 78 88
RH % (24H TREND) 90 (+1) 63 (-7) 90 62
WIND 20FT/EARLY(MPH) E 16 E 13 E 13 E 12
WIND 20FT/LATE(MPH) E 13 E 12 E 12 E 10
MIXING HGT(FT-AGL/MSL) 3010 2890
TRANSPORT WND (MPH) E 17 E 13
VENT RATE (KT-FT) 45150 31790
DISPERSION 5 5
DSI 6 6 6 6
RH RECOVERY EXCELLENT EXCELLENT
REMARKS...NONE.
VIZ002-180800-
ST CROIX-
330 PM AST THU SEP 17 2026
TONIGHT FRI FRI NIGHT SAT
CLOUD COVER PCLDY PCLDY PCLDY PCLDY
PRECIP TYPE SHOWERS SHOWERS SHOWERS SHOWERS
CHANCE PRECIP (%) 40 40 40 40
TEMP (24H TREND) 79 (-1) 90 (+2) 78 90
RH % (24H TREND) 91 (-2) 64 (-6) 89 62
WIND 20FT/EARLY(MPH) E 14 E 14 E 12 E 11
WIND 20FT/LATE(MPH) E 13 E 12 E 12 E 11
MIXING HGT(FT-AGL/MSL) 4560 4710
TRANSPORT WND (MPH) E 16 E 12
VENT RATE (KT-FT) 63840 47100
DISPERSION 5 5
DSI 6 6 6 6
RH RECOVERY EXCELLENT EXCELLENT
REMARKS...NONE.
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